2 bar E38 issues
Ok, I recently installed a magnacharger on my '07 GMC Sierra. I installed a 2 bar MAP sensor and properly scaled it in the computer. I also used the 2 bar Virtual VE(VVE) to update the coefficients. The MAF was also left installed.
The issue I am seeing with this setup is that the truck will not go over .8 g/cyl until 4000 rpm. It starts out lean13:1 and gets leaner14:1 as rpms increase until 4000 rpm also. This is all at WOT. Once it passes the 4000 rpm mark the g/cyl jump to 1.10 and the AFR goes down to 11.5 or so. The jump to 1.10 g/cyl is very obvious. I am not sure what happens at 4000 rpm but, the "high speed mode rpm"(B8024) is set to 4000 rpm so I have a feeling that has something to do with it. PE was set to .80 and 40% throttle. I also tried adjusting the VVE table with no effect.
I have went back to the stock 1 bar/MAF setup and am using PE for fueling over 40% TPS. The .8 g/cyl limit is not present with this setup. I can go WOT from a stop and almost instantly be over 1.00 g/cyl as boost rises.
Anyone have any ideas what is up with the 2 bar setup?
Here is the stock .tun file from the truck.
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